<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
        var obj = {
            name:'jack',
            age:20
        }    
        console.log(obj)
        function change(obj){
            obj.name='rose'
            obj.age = 18
        }

        var temp = {}
        temp.name = obj.name
        temp.age = obj.age
        change(temp)
        console.log(obj)
    </script>
</body>
</html>